Sitting on the plane a while later - still stuck on the tarmac - I checked my email to see the following message with the timestamp of 7:35:

Hi, Robert A Stribley.

JetBlue Airways (JetBlue) is now following your updates on Twitter.

Check out JetBlue Airways's profile here:

http://twitter.com/JetBlue

You may follow JetBlue Airways as well by clicking on the "follow" button.

Best,Twitter

Now, I will say that JetBlue put us on the plane about an hour and a half earlier than they'd earlier than they said they were going after they'd discussed the delays. I won't pretend to know that that had anything with my efforts - especially since the plane still ended up taking off at about 8:45, about 3 hours and 45 minutes after it was originally supposed to. But it does indicate at least that JetBlue knew what I was thinking at the time - even before my flight took off. So in that sense, Twitter worked for me.

Update: JetBlue responds to my post here in comments within 45 minutes. I'm impressed with your responsiveness to social media, JetBlue, if not always with your service!